George a



. G. A. Ek }0NESl APPARATUS FOR HEATING RIVETS.

APPLrcAnoN FILED APR.25.1919.

1,3 13,539,` s PatentedAug. 19,1919.

2 a g l .n quintali".

l llllll UNITED STATES PATENT OEEIOE.

GEORGE A. E. JONES, OF NEW LONDON, CONNECTICUT, ASSIGNOB TO UNITEDSTATES ELECTRIC COMPANY, CORPORATION' OF CONNECTICUT.

APPARATUS FOR HEATING RIVETS.

' Application filed April 25,

To all whom t may concern:

Be it known that I, GEORGE A. E'. JONES, a citizen of the United States,and a resident of New London and county of New London and State ofConnecticut, have invented an Improvement in Apparatus. for HeatingRivets, of Awhich the following description., in connection with theaccompanying drawings, is a specification, like reference'charf acterson the drawings representingk like, parts. f' This invention relates toan apparatusy for heating rivets by passing an electric.A currenttherethrough after the cold rivets have 'been inserted 1n the holes inthe struc-v tural arts to be united by them.

In atent No. 1,297,570 granted toA "me I March 18, 1919, I have shownvelectrodes-to vao be applied to the point and' head'ofjthe rivet,respectively, so that the current passiesV from one electrode to theother through-the rivet. In such construction, it is necessary to haveelectric connections from the electrodes to the transformer or source of-electric current at both sides of the structure in which the rivet iscontained and itis sometimes difficult to provide adequately for suchconnections.

In accordance with the present invention, I employ two electrodesconnected with the poles of the source of the electric current, andcooperating therewith at the other side of the structure, I employ abridging connector of large conductivity adapted to make contact withthe heads of two rlvets simultaneous] so that when the electrodes at theother s1de of the structure are placed in contact with the4 tips of thesaid rivets, the current passes from one electrode through thecorresponding rivet, to the connecting piece at the other end of saidrivet and thence to the other rivet, and through the same to the otherelectrode, the two rivets being thus interposed in series in theelectric circuit and being heated simultaneously.

The invention further consists in the combination of a movable electrodewith a rivet heading machine so that the same operator may irst a plythe electrode to the rivet to be heate and immediately upon withdrawalthereof afterv the rivet has been properly heated may apply the headingmachine to eiect the heading of the rivet.

Specication of Letters Patent.

Patented Aug. 19, 1919.

1919. serial No. 292,543. The invention further consists in providingthe electrode with internal'passages for the clrculation of coolingfluid, herein shown as adapted to be placed in communication with. theexhaust passage of a pneumatlc heading machine so that at the timewhen'the hammer of said machine is operating to head the rivet, theexhaust from the machine will be caused to vflow through the body oftheelectrode and coolthe same.

so that it will.- not become overheate'd as is liable to happen ifemployed for heating rivets in close succession without intervening`cooling.

igure 1, is a diagrammatic view illustratm a rivet heating apparatusemploy- 1ng. th1s invention, showing the rivet connetmng or bridgingconductor in section, an

Fig. 2, is as ectional detail on a .larger scale of `one oftheelectrodes adapted to be used in combination with a pneumatic rivetheading machine.

I teferring to Fig. 1, the electrodes 2, 20, which so far as one portionof the invention 1s concerned may be of an suitable construction such asis exempli ed in Patent No. 1,297,570 above referred to, are connectedby cables 3,'- 30, of largev conductivit with the opposite poles or.terminals of the Secondary component of a transformer 4, the primarwith e ectric` current from any convenlent source. Said electrodes areshown inthis instance as mechanicall connected, as will be hereinafterdescribed),I with rivet heading machines herein shown as pneumaticrivetlng hammers 5 of usual construction and ing connector 6 consistingof a main b y portion of copper or material of high conuctivity and oflarge sectional area, adapted to make contact with the heads of tworivets 50, 51 when inserted in the lates 52, 53, or structural parts tobe unite b the rivets, with their points rojecting beyond said plates atthe other slde of the structure from that at which the connecting bridge6 is located.

are employed in conjunction with a briggcomponent of which is :suppliedFor convenience and safety in manipulaheading machine at which thehammer therey of is to engage the rivet, said bracket having a guidingpassage 13, (see Fig. 2), in.

which the correspondnig electrode is longitudinally movable.

A spring 14 tends-to pull the electrode rearwardly relative to theheading Inachine and when free to act holds the said electrode with a.stop shoulder 1 4, (see Eig 2), against the guide 13, in which positionthe contacting tip of the electrode is some distance rearward from therivet engaging end of the heading machine and consequently doesnotinterfere with the free manipulation of said machine in heading therivet after it has been heated by the passage of the currenttherethrough. l

In the use of the apparatus the rivets are cold when inserted in therivet holes, and

the operator on the side `at which the heads are located presses thebridge against the heads of two rivets, thus providing a much lessresistant electric connection between them than what is afforded by theplates or structural partsv52, 53 in the'holes of which the rivets areinserted.

The operators at the other side of the structural parts 52, 53 then.press the elec trodes 2, 20, against the projecting 'ends of the tworivets, the heads of which are bridged |by the connector 6, the saidelectrodes 'being moved into and held in forward. position relative tothe heading machine as is permittedV by the expansion 'of the springs 14so that the heading machines will not interferewith the properapplication of the electrodes to the `ends of the rivets.

The current from the transformer then flows through the two rivets inseries and quickly hea-ts thesame to the proper teinperature an'dsotness for the heading operation whereupon the electrodes 2, 20 arereleased and are drawn back ouat of the way by the springs 14 and theheading machines 5 are -applied to the tips ofthe rivets and set inoperation to 4head the'rivets in the usual wav. a suiitable abutment orholder-on being appliedto the rivet head.

Referring to Fig. 2 which shows the construction of one of theelectrodes such as 2 or 20 em loyd 1n connection with a pneumatic riveteading machine, it wiill be seen that the main body portion is in closedin an insulating cover 21,v which is in turn inclosed in a protectingshield 22 which may be of iron, the electrode being in this respectsubstantially like that shown in my foi-nier patent, hereinbeorereferred to.

In accordance with the present invention however the main lbody portion2 of the electrode is provided wiith internal passages 25, 26,distributed through it, the passages 26 Ibeing shown as communicatingWi-th a space 27 surrounding the body 2 within the insulating covering21, the said space or jacket communicating by passages 28 near theprojecting contacting end yof the electrode with the surroundingatmosphere.

The passage 25 is adapted to receive a cooling fluid, .to be passedthrough the passages 25,26, and jacket space 27 from which it may bedischarged through the passages 28. In the present example of theinvention, Y, said fluid inlet [passage 25 is `connected'byl--a`v exiblepipe 24C with the `exhaust passage of! ythe pneumatic rivet headingmachine', the".- result oeing that when salid machine `i'sfiitoperationheading the rivet, the exhaust there-.-l from will be caused fto flowthrough the pas# sages 25, 26 and the jacket space 27, and to 90 escapeby the ypassages 28 to the atmosphere, thus cooling the main body oftheelectrode, so that it ydoes not become overheated as is liable to occurif employed to heat several rivets in succession 4with only 'suchintervals 95 between the heating operations as may ibe occupiedinperforming the heading opera'- tion, which in practice requires only asmall fraction of a'ininu-te for its performance.

The hose for supplying the compressed air by which .the heading machineis operated is indicated at, 29. Y

The bridging connector 6 is shown as provided With aslightly projectingledge 60 across one end and along one vside of the .105 contacting face,which aiords a slight shoulder projecting from the contacting face,which may engage with .the head of the rivet. when in an ap roXimatelyvertical plane, thus sustaining the weight of the connector and makin iteasier for the operator to keep it presse in contact with the rivetheads without liability of slipping oi.

For an embodiment of that part of the invention which provides for theheating of two rivets simultaneously, it is not essential that theelectrodes 2, 20 should be constructed as described,'or that one or bothof them should be combined or mechanically associated with a headingmachine as shown, and in some cases it may be desirable to use but oneheading machine in connection with two electrodes, the heading machinebeing employed to head the rivets consecutively tively of a suitablesource of electric currgent,l

and a bridging connecting piece ofjlarge conductivity adapted to beplacedfin' con-V tact with the heads of the two rivets with the tipsofwhich the electrodes"'are` to mak contact, substantially as described.i

2. The combination witha portable rivet heading machine, of anelectrode, and supporting and guiding 'means therefor; connected withsaid heading machine, said `electrode. being movable relativetor theheading machine, whereby the contacting end of the electrode may beadvanced beyond the end of the heading machine 0r withdrawn to the rearthereof. i

3. The combination of a rivet heading machine, with a contact electrodeand'guiding support therefor connected with said heading machine, saidelectrode being mova-ble to advance its contacting end beyond the end ofthe heading machine, and a spring to retract said electrode, and Stop tolimit the ymovement under the action of said spring, slibstantially'asdescribed.` Y j 54. An' electrode forv heating rivets com "prising amain body portion of conducting material yand a protecting shieldsurroundin the same with an inclosed Ispacebetween said electrode bodyand shield, saidy electrode body: being providedI with a longitudinalinternal pass e and with 'a number of passages connectlng the same withthe space within the shield, and there being passages from said space tothe external air, su v40 stantially as and for the purpose described. v

5. The combination with a pneumatic vheading machine, of anelectrode,"and supportingand iding means therefor connected with saidheading machine, said elec trode being provided with internalcirculating passages communicating with the exhaust passage of theheading machine, sub stantially as and for the purpose described. Intestimonywhereof, I have signed my name to this specification.

GEORGE A. JONES.

